The United Nations torture investigator says he has been blocked from visiting Cuba to look into allegations of human rights abuses.

Manfred Nowak said Wednesday he was disappointed when Cuba informed him they would be unable to accommodate his mission before his term ends several months from now on October 30.

Nowak said Cuba had issued a "clear invitation" to allow him to assess the torture situation on the ground, but repeated attempts to schedule the trip had been blocked.

There was no immediate comment from Cuba.

Last week, the U.S.-based human rights group Freedom House named Cuba among the top 20 worst human rights abusers in the world, saying it and the other listed countries severely suppress political opposition, independent organization, and criticism of the state.